Kerrian Peter A, Hanford Amanda D, Capone Dean E, Beck Benjamin S
ATA Acoustics, San Diego, California 92128, USA.
The Applied Research Laboratory at the Pennsylvania State University, State College, Pennsylvania 16801, USA.
J Acoust Soc Am. 2019 Oct;146(4):2303. doi: 10.1121/1.5127844.
One of the commonly investigated transformation acoustic device is the ground cloak, which conceals a scattering object on a reflecting surface. Multiple studies have numerically simulated acoustic ground cloaks, but because of the challenges associated with realizing a homogeneous anisotropic metamaterial, only two acoustic ground cloaks have been built and tested. Perforated plastic plates in air were used to construct two and three dimensional ground cloaks and alternating layers of brass and water were used to construct an extended area ground cloak underwater. With underwater mass density anisotropy previously demonstrated for perforated steel plates, the primary focus of this article is to build and evaluate an underwater ground cloak with perforated steel plates. The cloak was evaluated at a water-air pressure release reflecting surface. The cloak successfully concealed the scattering object over a broad frequency range of 7-12 kHz.
一种常见的被研究的变换声学装置是地面隐身衣，它能在反射面上隐藏一个散射物体。多项研究对声学地面隐身衣进行了数值模拟，但由于实现均匀各向异性超材料存在挑战，仅有两件声学地面隐身衣被制造并测试。空气中的穿孔塑料板被用于构建二维和三维地面隐身衣，而黄铜和水的交替层被用于在水下构建一个扩展区域的地面隐身衣。鉴于此前已证明穿孔钢板具有水下质量密度各向异性，本文的主要重点是制造并评估一件由穿孔钢板制成的水下地面隐身衣。该隐身衣在水 - 空气压力释放反射面上进行了评估。该隐身衣在7 - 12千赫兹的宽频率范围内成功隐藏了散射物体。
